Hydrogen Conversion Research Articles

Insight into the structural sensitivity of CuZnAl catalysts for CO hydrogenation to alcohols

The catalytic conversion of CO hydrogenation is a structure-sensitive reaction over Cu-based catalyst. It is very important to distinguish the structural differentiation and possible reaction pathway of Cu-based catalysts in methanol synthesis and ethanol/C2+OH synthesis. Herein, the activity of four types of CuZnAl catalysts is evaluated, and their structural differentiation is investigated. The CuZnAl catalyst (CZA) prepared by a complete liquid-phase (CLP) method after solid–liquid separation directly applied in the fixed bed reactor also shows the ability to synthesize ethanol and higher alcohols (C2+OH), with the selectivity of C2+OH in liquid product reaching up to 31.6% at the CO conversion of 10.6%. However, commercial methanol synthesis catalyst (CMC) displays the highest CO conversion (28.2%) and the poorest C2+OH selectivity (7.8%). After characterized by ICP, XRD, CO-TPD, N2O adsorption, XPS, SEM, TEM and in-situ DRIFTS techniques, it is discovered that the dispersion of Cu and the exposed Cu surface area significantly influences CO conversion. The selectivity of ethanol and C2+OH is related to the size and distribution of Cu, the architectural feature, and the chemical environment of Cu and Al. In-situ DRIFTS indicates that CHxO* species can be formed over different CuZnAl catalysts. However, the formed CHxO* species will be rapidly hydrogenated to produce methanol on CMC catalyst, while the step is inhibited on CZA catalyst. Additionally, a bridge-type adsorbed CO is only observed on CZA catalyst, which is beneficial for the formation of CHx intermediates, leading to the formation of ethanol and higher alcohols.

Using Hydrogen Reactors to Improve the Diesel Engine Performance

This work is aimed at solving the problem of converting diesel power drives to diesel–hydrogen fuels, which are more environmentally friendly and less expensive alternatives to diesel fuel. The method of increasing the energy efficiency of diesel fuels has been improved. The thermochemical essence of using methanol as an alternative fuel to increase energy efficiency based on the provisions of thermotechnics is considered. Alternative methanol fuel has been chosen as the initial product for the hydrogen conversion process, and its energy value, cost, and temperature conditions have been taken into account. Calculations showed that the caloric effect from the combustion of the converted mixture of hydrogen H2 and carbon monoxide CO exceeds the effect from the combustion of the same amount of methanol fuel. Engine power and fuel energy were increased due to the thermochemical regeneration of engine exhaust gas heat. An experimental setup was created to study the operation of a converted diesel engine on diesel–hydrogen products. Experimental studies of power and environmental parameters of a diesel engine converted for diesel–hydrogen products were performed. The studies showed that the conversion of diesel engines to operate using diesel–hydrogen products is technically feasible. A reduction in energy consumption was accompanied by an improvement in the environmental performance of the diesel–hydrogen engine working together with a chemical methanol conversion thermoreactor. The formation of carbon monoxide occurred in the range of 52–62%; nitrogen oxides in the exhaust gases decreased by 53–60% according to the crankshaft speed and loading on the experimental engine. In addition, soot emissions were reduced by 17% for the engine fueled with the diesel–hydrogen fuel. The conversion of diesel engines for diesel–hydrogen products is very profitable because the price of methanol is, on average, 10–20% of the cost of petroleum fuel.

A comparison study on aluminum-water reaction with different catalysts

The aluminum-water reactions with various organic and inorganic catalysts have been investigated. The effect of catalyst on the rate and yield of hydrogen production and morphology and structure of Al(OH)3 product has been studied. The difference in reaction rate and hydrogen conversion efficacy is mainly ascribed to the ability to destroy alumina film and alkalinity of the catalyst solutions, and the hydrogen conversion efficiency of Al with tetramethylguanidine is the highest. The morphology and structure of the Al(OH)3 product are also characterized. The main phases of Al(OH)3 product prepared by these catalysts are Bayerite and Gibbsite. The morphologies and size distributions of Al(OH)3 products are different. The largest (D50, 64.0 µm) and smallest (D50, 20.8 µm) particle sizes of Al(OH)3 are prepared by the Al-H2O reactions with KOH and tetramethylguanidine, respectively. The role of catalyst in the Al-H2O reaction is discussed in detail.

Combined thermoacoustic cooling and ortho-para conversion of cryogenic hydrogen

Hydrogen is a promising fuel for our future, as it can be produced with renewable energy sources and it does not emit harmful emissions when reacting with oxygen. To make the hydrogen economy viable, hydrogen needs to be transported as a dense cryogenic liquid. Since efficiencies of current cryocoolers are relatively low, improvements of the cooling technologies are required. In this study, an innovative solution involving thermoacoustic flow-through cooler is considered. Acoustic waves passing through porous medium can pump heat and cool hydrogen flowing through the system. An important feature of cryogenic hydrogen is the shift between its equilibrium ortho and para isomer fractions, which requires additional removal of heat. Since the natural conversion is slow, it must be augmented by catalysts for fast transition. The advantage of using the flow-through thermoacoustic system to cool hydrogen is that a catalyst can be placed in the porous matrix where hydrogen flows, so it can be cooled and undergo conversion at the same time. A mathematical model describing this process has been developed. Results showing achievable coefficients of performance, temperature drops, and flow rates of hydrogen are presented for both standing-wave and travelling-wave systems.

The local PNG bias of neutral Hydrogen, HI

We use separate universe simulations with the IllustrisTNG galaxy formation model to predict the local PNG bias parameters bΦ and bΦδ of atomic neutral hydrogen, HI. These parameters and their relation to the linear density bias parameter b 1 play a key role in observational constraints of the local PNG parameter f NL using the HI power spectrum and bispectrum. Our results show that the popular calculation based on the universality of the halo mass function overpredicts the bΦ (b 1) and bΦδ (b 1) relations measured in the simulations. In particular, our results show that at z ≲ 1 the HI power spectrum is more sensitive to f NL compared to previously thought (bΦ is more negative), but is less sensitive at other epochs (bΦ is less positive). We discuss how this can be explained by the competition of physical effects such as that large-scale gravitational potentials with local PNG (i) accelerate the conversion of hydrogen to heavy elements by star formation, (ii) enhance the effects of baryonic feedback that eject the gas to regions more exposed to ionizing radiation, and (iii) promote the formation of denser structures that shield the HI more efficiently. Our numerical results can be used to revise existing forecast studies on f NL using 21 cm line-intensity mapping data. Despite this first step towards predictions for the local PNG bias parameters of HI, we emphasize that more work is needed to assess their sensitivity on the assumed galaxy formation physics and HI modeling strategy.

Role of surface morphology and terminating groups in titanium carbide MXenes (Ti3C2Tx) cocatalysts with engineering aspects for modulating solar hydrogen production: A critical review

• Current progress of Ti 3 C 2 MXene as prominent materials for hydrogen production is reviewed. • Insight into structural and catalytic properties of Ti 3 C 2 MXene are summarized. • Design of Ti 3 C 2 MXene with 0D, 1D, 2D and 3D dimensions are deliberated. • The control of surface termination groups in Ti 3 C 2 MXene are discussed. • Photocatalytic reaction engineering improvement through morphological modulation are systematically reviewed. Hydrogen production through photoinduced water splitting is regarded as one of the best alternatives in providing clean and renewable energy sources. Recently, MXene as co-catalysts are considered promising green structured materials to replace expensive noble metals to promote both efficiency and photostability. The utilization of titanium carbide (Ti 3 C 2 T x ) MXene as a co-catalyst has shown great promise for assisting solar to hydrogen conversion owing to their structural flexibility, surface morphological, and tailorable termination groups. The surface functional groups, morphological developments and engineering aspects are important factors to optimize Ti 3 C 2 T x as the best co-catalyst in solar energy applications. This review provides recent advances in morphological design of Ti 3 C 2 T x MXene with critical analysis on the role of termination groups for promoting photoactivity and products selectivity. A deep focus is given to the engineering design of Ti 3 C 2 T x MXene with special regard to quantum dots, monolayer, and hierarchical structures. Firstly, the general overview of Ti 3 C 2 T x MXene is introduced with insights into their catalytic properties and formation of surface termination groups to gain profound understanding of their basic catalytic structure. Next, the effects of tailoring the morphology of Ti 3 C 2 T x MXene into 2D accordion-like structure, monolayer, hierarchical, quantum dots, and nanotubes structure to expedite their role to promote solar-based photoactivity are critically discussed. In addition, specific considerations are given on the effects of reaction parameters, challenges, and synthesis strategies for tailoring the morphology of Ti 3 C 2 T x MXene with controlled functional groups. Finally, future perspectives are provided for the potential use of Ti 3 C 2 T x MXene as green materials in reaction engineering and environment applications.

Bi2S3 entrenched BiVO4/WO3 multidimensional triadic photoanode for enhanced photoelectrochemical hydrogen evolution applications

The catalytic reactivity and photoactivity of WO 3 and BiVO 4 oxide semiconductors have general obstacles as electrodes in emergent photo-electrochemical (PEC) hydrogen evolution applications. The present work comprises the integration of photocatalyst with wide visible photon absorption material which is vital for hydrogen evolution in photo-electrocatalytic water splitting. Herein, the 1D WO 3 NWs have been integrated with stable water oxidation photocatalysts of BiVO 4 and Bi 2 S 3 as a photoanode (Bi 2 S 3 /BiVO 4 /WO 3 ) for photoelectrochemical hydrogen evolution reactions. The morphological variations in the Bi 2 S 3 /BiVO 4 /WO 3 heterostructure manifest catalytic activity and rapid charge transfer characteristics owing to band alignment and a wide range of visible photon absorption. The optimized Bi 2 S 3 /BiVO 4 /WO 3 multidimensional photoanode accomplishes a superior photocurrent density of 1.52 mA/cm 2 , a seven-fold higher than pristine WO 3 photoanode counterpart (0.2 mA/cm 2 ) at 1 V vs. RHE. A prodigious lowest onset potential of −0.01 V vs. RHE) has been achieved which enables very high solar to hydrogen conversion. The photoelectrode with entangled morphology such as nanosheets, nanocrystals and nanorods expanded their surface to volume ratio having enhanced catalytic performance. The hybrid photoanodes have demonstrated the lowest charge transfer resistance of 360 Ohm/cm 2 with a 7-fold rise in hydrogen evolution performance. The resultant triadic Bi 2 S 3 /BiVO 4 /WO 3 heterostructure appeared to be an emerging stable photo-electro catalyst for hydrogen evolution applications. • A multidimensional Bi 2 S 3 /BiVO 4 /WO 3 is prepared by hydrothermal and SILAR method. • The hetero-structure upholds photo-excitation and enhances carriers' kinetics. • The open triadic structure improves the hydrogen evolution. • A type II band alignment in Bi 2 S 3 /BiVO 4 /WO 3 hetero-structure is proposed.

Round-the-clock bifunctional honeycomb-like nitrogen-doped carbon-decorated Co2P/Mo2C-heterojunction electrocatalyst for direct water splitting with 18.1% STH efficiency

Hydrogen production via solar and electrochemical water splitting is a promising approach for storing solar energy and achieving a carbon-neutral economy. However, hydrogen production by photoelectric coupling remains a challenge. Here, by the cooperative coupling of heteroatoms and a heterojunction interface engineering strategy in a limited space, a honeycomb porous Co2P/Mo2C@NC catalyst was obtained for the first time. In contrast most traditional chemical syntheses, this method maintains excellent electrical interconnections among the nanoparticles and results in large surface areas and many catalytically active sites. Theoretical calculations reveal that the construction of a heterostructure can effectively lower the hydrogen evolution reaction and oxygen evolution reaction barriers as well as improve the electrical conductivity, consequently enhancing the electrochemical performance. Significantly, the overall water-splitting hydrolytic tank assembled using AsGa solar cells enabled the system to achieve a stable solar hydrogen conversion efficiency of 18.1%, which provides a new approach for facilitating large-scale hydrogen production via portable water hydrolysis driven by solar cells.

Thermal and chemical analysis on the hetero-/homogeneous combustion characteristics of H2/Air mixture in a micro channel with catalyst segmentation

The heterogeneous-homogeneous combustion characteristics of premixed H2/Air mixture in a micro combustor with 2 mm platinum (Pt) catalyst segmentation are investigated by numerical simulation. The detailed chemical reaction mechanisms of gas-phase reaction and surface reaction of H2 are employed in a 2D CFD model by the verification. The characteristics in the catalytic combustor, such as temperature distribution, species concentration, kinetics reaction rate and heat transfer, are examined by varying inlet flow velocities. There is an interesting fact that an obvious demarcation line splits the channel into two regions at high velocities, which are dominated by heterogeneous reaction (Htr) and homogeneous reaction (Hr). In addition, there is a coupling heterogeneous-homogeneous reaction (HHr) in the 2 mm downstream of the catalytic region. These should be thoroughly deliberated using thermal and chemical analyses to determine that the gaseous flame is against the Htr in the catalytic combustor. The results can be shown that the heat flux into the upstream catalytic wall is primarily due to exothermicity induced by Htr. A low amount of heat feedback via the solid wall to inlet wall which is released by Hr. The heat fluxes from the gas–solid interface preheat the fresh gaseous mixture in the channel, thereby promoting the occurrence of Hr, increasing the heat release rate and kinetic reaction rate of Hr. Moreover, heat feedback from the heat release of Hr through the solid wall increases the reaction rates of Htr. The hydrogen conversion rate is improved by the effect of Htr in the catalytic combustor. In summary, the effect of introducing catalytic surface to induce the Htr could be well suitable for micro combustion schemes.

Stepwise dechlorination of chlorinated alkenes on an Fe-Ni/rGO/Ni foam cathode: Product control by one-electron-transfer reactions

Research on the stepwise hydrogenation dechlorination of chlorinated alkenes forms an important basis for eliminating toxic intermediate incomplete dechlorination products. The low-cost Fe-Ni/rGO/Ni foam cathode both supplied electrons and exhibited hydrogen conversion activity, and it was an excellent tool for the study of stepwise dechlorination. Electrochemical reduction experiments were carried out on homologous chlorinated alkenes. The conditions affecting the dechlorination efficiency and the repeatability of the catalytic electrode were analyzed. The trichloroethylene (TCE) removal rates were all above 78.0% over 8 cycles. The maximum EHDC efficiency was as high as 86.1%, and the faradaic efficiency was over 78.8%. Electrochemical methods combined with the calculation of the electron transfer number are proposed to verify the good hydrogenation ability of the electrode and the stepwise reduction ability at proper voltages. The stepwise dechlorination electroreduction characteristics of chlorinated alkenes were explained. The C-Cl bond dissociation enthalpies of chlorinated alkenes were calculated by density functional theory (DFT), and the 4-Cl and 5-Cl of TCE were expected to be removed first. The stepwise cleavage of chlorinated alkenes on Fe-Ni/rGO/Ni foam during dichlorination provided a reference for controlling the reduction products of chlorinated alkenes and preventing the pollution caused by toxic intermediate products formed during incomplete dechlorination.

Strain Adjustment Realizes the Photocatalytic Overall Water Splitting on Tetragonal Zircon BiVO4.

Overall water splitting to generate H2 and O2 is vital in solving energy problem. It is still a great challenge to seek efficient visible light photocatalyst to realize overall water splitting. In this work, the tetragonal zircon BiVO4 is prepared by epitaxial growth on FTO substrate and its overall water splitting reaction is studied. Under the influence of epitaxial strain, the conduction band position shifts negatively and beyond H+/H2 reduction potential (0 V vs NHE), which enables it to possess the photocatalytic hydrogen evolution activity. After loading cocatalysts, the overall water splitting (λ > 400 nm) is realized (H2: ≈65.7 µmol g−1 h−1, O2: ≈32.6 µmol g−1 h−1), and the value of solar hydrogen conversion efficiency is 0.012%. The single‐particle photoluminescence (PL) spectra and PL decay kinetics tests demonstrate the cocatalysts are beneficial to the separation and transfer of carriers. The new strategy of adjusting the band structure by strain is provided.

Optimal operation of geothermal-solar-wind renewables for community multi-energy supplies

This paper proposes a geothermal-solar-wind renewable energy hub framework for community multi-energy supplies. In this framework, multi-energy complementarities of geothermal-solar-wind hybrid renewable energy are fully explored based on electrolytic thermo-electrochemical effects of geothermal-to-hydrogen (GTH), which is integrated with the multi-energy conversion and storage devices for multi-energy supplies. In order to exploit the inherent multi-energy operational dispatchability and flexibility of geothermal-solar-wind renewables, a multi-energy coupling matrix is formulated for the modeling of production, conversion, storage, and consumption of hub-internal electricity, hydrogen and heating energy. A multi-energy operation scheme is further developed to dispatch the energy flows of the coupling matrix for cost-effective accommodation of community renewables. Case studies on a community microgrid under grid-connected and grid-disconnected modes are performed to verify the effectiveness and superiority of the proposed methodology. Simulations results show that the solar-wind accommodation can be improved by at most 1.59% with a significantly lower system operating cost.

Model Supported Business Case Scenario Analysis for Decentral Hydrogen Conversion, Storage and Consumption within Energy Hubs

Recently, smart energy hubs with hydrogen conversion and storage have received increased attention in the Netherlands. The hydrogen is to be used for vehicle filling stations, industrial processes and heating. The scientific problem addressed in this paper is the proper sizing of capacities for renewable energy generation, hydrogen conversion and storage in relation to a feasible business case for the energy hub while achieving security of supply. Scenario analysis is often used during the early stages of the energy planning process, and for this an easy-to-use analysis model is required. This paper investigates available modelling approaches and develops an algorithmic modelling method which is worked out in Microsoft Excel and offers ease of use for scenario analysis purposes. The model is applied to case study, which leads to important insights such as the expected price of hydrogen and the proper sizing of electrolyser and hydrogen storage for that case. The model is made available open-source. Future work is proposed in the direction of application of the model for other project cases and comparison of results with other available modelling tools.

Band Structure Engineering and Defect Passivation of Cu x Ag1-x InS2/ZnS Quantum Dots to Enhance Photoelectrochemical Hydrogen Evolution.

The AgInS2 colloidal quantum dot (CQD) is a promising photoanode material with a relatively wide band gap for photoelectrochemical (PEC) solar-driven hydrogen (H2) evolution. However, the unsuitable energy band structure still forms undesired energy barriers and leads to serious charge carrier recombination with low solar to hydrogen conversion efficiency. Here, we propose to use the ZnS shell for defect passivation and Cu ion doping for band structure engineering to design and synthesize a series of CuxAg1–xInS2/ZnS CQDs. ZnS shell-assisted defect passivation suppresses charge carrier recombination because of the formation of the core/shell heterojunction interface, enhancing the performance of PEC devices with better charge separation and stability. More importantly, the tunable Cu doping concentration in AgInS2 CQDs leads to the shift of the quantum dot band alignment, which greatly promotes the interfacial charge separation and transfer. As a result, CuxAg1–xInS2/ZnS CQD photoanodes for PEC cells exhibit an enhanced photocurrent of 5.8 mA cm–2 at 0.8 V versus the RHE, showing excellent photoelectrocatalytic activity for H2 production with greater chemical-/photostability.

Hydrofluoroolefin-based mixed refrigerant for enhanced performance of hydrogen liquefaction process

Hydrogen has the highest gravimetric energy density of all fuels; however, it has a low volumetric energy density, unfavorable for storage and transportation. Hydrogen is usually liquefied to meet the bulk transportation needs. The exothermic interconversion of its spin isomers is an additional activity to an already energy-intensive process. The most significant temperature drop occurs in the precooling cycle (between −150 °C and up to −180 °C) and consumes more than 50% of the required energy. To reduce the energy consumption and improve the exergy efficiency of the hydrogen liquefaction process, a new high-boiling component, Hydrofluoroolefin (HFO-1234yf), is added to the precooled mixed refrigerant. As a result, the specific energy consumption of precooling cycle reduces by 41.8%, from 10.15 kWh/kgLH2 to 5.90 kWh/kgLH2, for the overall process. The exergy efficiency of the proposed case increases by 43.7%; however, the total equipment cost is also the highest. The inflated cost is primarily due to the added ortho-to-para hydrogen conversion reactor, boosting the para-hydrogen concentration. From the perspective of bulk storage and transportation of liquid hydrogen, the simplicity of design and low energy consumption build a convincing case for considering the commercialization of the process.

Abundance ratio of multiple velocity distribution components in a single negative ion beamlet produced by a cesium-seeded negative ion source

Well focused negative ion beams are required for neutral beam injection systems for heating and current drive in magnetically confined fusion plasma experiments. The control of a single negative ion beamlet divergence is a significant challenge with the use of a cesium-seeded negative ion source, where negative ions are mainly produced by conversion of hydrogen or deuterium atoms on a cesiated surface of a plasma grid. The single negative ion beamlet was found to be made by three-Gaussian components in our previous work. The origins of such multiple components are considered to be related to dynamics in the ion source and extraction processes of negative ions. This work has demonstrated a measurement of the abundance ratio of the three components (41%, 40%, and 19%) based on a full picture of their transverse velocity distributions, which is a powerful technique to investigate the origins of individual components and will contribute to improve the divergence of negative ion beamlet.

A direct Z-scheme MoSi2N4/BlueP vdW heterostructure for photocatalytic overall water splitting

Building novel van der Waals (vdW) heterostructures is a feasible method to expand material properties and applications. A MoSi2N4/blue phosphorus (BlueP) heterostructure is designed and investigated as a potential photocatalytic candidate by first-principle calculations. Based on the band alignment and electron transfer, MoSi2N4/BlueP exhibits the characteristics of direct Z-scheme vdW heterostructure, which is favorable for the spatial separation of photogenerated carriers and retains a strong redox capacity. Moreover, the MoSi2N4/BlueP possesses suitable band-edge positions for overall water splitting. Compared with the light absorption of two monolayer materials, the heterostructure has a stronger light absorption from the visible to ultraviolet region. The solar to hydrogen conversion efficiency can reach 21.1% for the heterostructure, which is over three-fold and four-fold as great as that of pristine MoSi2N4 and BlueP monolayers, respectively. All the results show that the MoSi2N4/BlueP heterostructure is a promising photocatalyst for overall water splitting, and it provides new possibilities for designing high-efficiency photocatalysts.

Cuprous oxide single-crystal film assisted highly efficient solar hydrogen production on large ships for long-term energy storage and zero-emission power generation

Designing and manufacturing green ships and achieving zero emissions is one of the important trends in modern society for energy conservation and emission reduction. This article explores a novel combined technology of photovoltaic and photoelectrocatalysis to achieve efficient solar hydrogen production, in which the onset voltage for solar water splitting moved from 1.23 V forward to 0.59 V under the assistance of p-Cu2O single-crystal film. After implementing on a 110-m barge for the first time, a solar to hydrogen conversion efficiency of 9.79% has been achieved, which is state-of-the-art in large practical projects, producing 63 Nm3 of hydrogen every day accompanied with an outstanding Faraday efficiency higher than 98.2%. The hydrogen has been purified and compressed for storage, then generates 96 kWh of electricity on demand through the fuel cell stack (43% efficiency). The hydrogen-powered ship can reduce 6.1 tons of diesel consumption and 18.9 tons of carbon dioxide emissions each year.

Ultra‐Durability and Enhanced Activity of Amorphous Cobalt Anchored Polyaniline Synergistic towards Electrocatalytic Water Oxidation

AbstractCobalt anchored polyaniline electrocatalysts (Co@PANI) have been synthesized (Co@PANI‐200, Co@PANI‐400, Co@PANI‐600, Co@PANI‐800) and characterised. The electrical conductivity and stability of Co@PANI increased due to the synergistic effect of PANI and cobalt content. PANI prevents aggregation and show strong binding with cobalt ions. The Co@PANI‐600/GC shows low overpotential of 341 mV @ 10 mA cm−2 current density and the Tafel slope of Co@PANI‐600 (39 mV dec−1) was smaller than IrO2 (98 mV dec−1) for OER. The calculated turnover frequency (TOF) of Co@PANI‐600/GC (0.01609 s−1) was ≈8 times higher than IrO2 (0.0014 s−1) at 1.60 V. Furthermore, the Co@PANI‐600/NF electrocatalyst shows an incredibly low overpotential of 251 mV @10 mA cm−2. This new born Co@PANI‐600/NF exhibits durability over 250 h with only 5.1 % potential loss in alkaline medium. Co@PANI‐600 catalyst exhibits excellent OER performances as well as having enough kinetics to solve the sluggish rate of water oxidation. At 1.54 V, the solar driven water electrolysis demonstration supports the efficiency of new born electrocatalyst in solar to hydrogen conversion. These research findings confirm that Co@PANI‐600 can be used for large‐scale hydrogen generation at the lowest possible cost.

Magnetic Method for Rapid Detection of Carburization Degree of Fe–Cr–Ni Series High-Temperature Heat-Resistant Alloy

Abstract Rapid detection technology of the carburization of Fe–Cr–Ni high-temperature heat-resistant alloys in the ethylene cracking furnace and the hydrogen conversion furnace is in great need to prevent industrial accident. This paper implemented the GMRI-I carburizing detector to test the degree of carburization of 25Cr35NiNb+ microalloy inlet tube and 35Cr45NiNb+ microalloy outlet tube of the ethylene cracking furnace after service as well as the reinforced joint made of UNS N08810 from the hydrogen-producing reformer. In conjunction with the results of the low-power acid corrosion test, a rapid detection method for the degree of carburization was proposed. Based on the experimental results of the carburizing detector and the laboratory test data, the carburization degree test curve of the above three alloys based on the magnetic field strength has been established. The detection accuracy was circa. 5% and the error was ±10%, which is convenient for guiding the use and replacement of Fe–Cr–Ni high-temperature heat-resistant alloy materials for ethylene cracking furnace and hydrogen conversion furnace, thereby ensuring the safe and stable operation of the device.